Kiniksa Pharmaceuticals Reports Third Quarter 2022 Financial Results and Provides Corporate Update - ARCALYST (rilonacept) Q3 2022 net revenue of $33.4 million - - RHAPSODY long-term extension data demonstrated rilonacep

Pharmaceuticals Reports Third Quarter 2022 Financial Results and Provides Corporate Update

ARCALYST (rilonacept) Q3 2022 net revenue of $33.4 million -

RHAPSODY long-term extension data demonstrated rilonacept treatment beyond 18 months resulted in continued treatment response (Hazard

Ratio = 0.018, p<0.0001) -

KPL-404 Phase 2 data in rheumatoid arthritis expected in 1H 2024 -

Cash reserves of $200.7 million expected to fund operations into at least 2025 -

Conference call and webcast scheduled for 8:30 am ET today -

BERMUDA - November 1, 2022

- Kiniksa Pharmaceuticals, Ltd. (Nasdaq: KNSA) (Kiniksa), a biopharmaceutical company with a portfolio of assets designed

to modulate immunological pathways across a spectrum of diseases, today reported third quarter 2022 financial results and provided a

"Physician adoption,

patient satisfaction, and payer access drove continued strong ARCALYST performance in the third quarter. We remain focused on positioning

ARCALYST as the standard of care for recurrent pericarditis, with the goal of broadening our reach and helping even more patients,"

said Sanj K. Patel, Chairman and Chief Executive Officer of Kiniksa. "Additionally, with the profitable ARCALYST collaboration

and initial proceeds from the global license agreement with Genentech for the rights to develop and commercialize vixarelimab, we are

well-positioned to execute on synergistic growth opportunities across our portfolio, including the expansion of our ARCALYST cardiovascular

and IL-1 cytokine trap)

antibody inhibitor of CD40-CD154 interaction)

Mavrilimumab (monoclonal

antibody inhibitor targeting GM-CSFR )

Scientific Conference Presentation

Imazio of University Hospital Santa Maria della Misericordia, Udine, will present a poster presentation entitled Prolonged Rilonacept

Treatment in RHAPSODY Long-Term Extension Provided Persistent Reduction of Pericarditis Recurrence Risk on Sunday, November 6, 2022,

from 3:45 to 4:45 p.m. Central Time (4:45 - 5:45 p.m. Eastern Time).

in the abstract are as of the abstract cutoff date; final data are under embargo until the poster presentation.

3 Upon commercial availability

of ARCALYST for recurrent pericarditis in April 2021, the LTE portion in the US ended, and patients continuing therapy transitioned to

commercial ARCALYST. Non-US patients remained in the LTE without interruption until the LTE closed in June 2022.

is a biopharmaceutical company focused on discovering, acquiring, developing, and commercializing therapeutic medicines for patients

suffering from debilitating diseases with significant unmet medical need. Kiniksa's portfolio assets, ARCALYST, KPL-404, and mavrilimumab,

are based on strong biologic rationale or validated mechanisms, target underserved conditions, and offer the potential for differentiation.

These assets are designed to modulate immunological pathways across a spectrum of diseases. For more information, please visit www.kiniksa.com.

is a weekly, subcutaneously injected recombinant dimeric fusion protein that blocks interleukin-1 alpha (IL-1 ) and interleukin-1

beta (IL-1 ) signaling. ARCALYST was discovered by Regeneron and is approved by the U.S. Food and Drug Administration (FDA) for

recurrent pericarditis, cryopyrin-associated periodic syndromes (CAPS), including Familial Cold Autoinflammatory Syndrome and Muckle-Wells

Syndrome, and deficiency of IL-1 receptor antagonist (DIRA). The FDA granted Breakthrough Therapy designation to ARCALYST for the treatment

of recurrent pericarditis in 2019 and Orphan Drug designation to ARCALYST for the treatment of pericarditis in 2020. The European Commission

granted Orphan Drug Designation to ARCALYST for the treatment of idiopathic pericarditis in 2020.

ARCALYST is indicated

SAFETY INFORMATION ABOUT ARCALYST

more information about ARCALYST, talk to your doctor and see the Product Information.

is an investigational humanized monoclonal antibody that is designed to inhibit CD40-CD154 (CD40 ligand) interaction, a key T-cell co-stimulatory

signal critical for B-cell maturation and immunoglobulin class switching and Type 1 immune responses. Kiniksa believes disrupting the

CD40-CD154 interaction is an attractive approach to address multiple autoimmune disease pathologies.

is an investigational fully human monoclonal antibody that blocks activity of GM-CSF by specifically binding to the alpha subunit of

the GM-CSF receptor (GM-CSFR ). Phase 2 clinical trials of mavrilimumab in rheumatoid arthritis and giant cell arteritis achieved

their primary and secondary endpoints with statistical significance. Kiniksa is evaluating the development of mavrilimumab in rare cardiovascular

diseases where the GM-CSF mechanism has been implicated.

Forward-Looking Statements

This press release contains

forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. In some cases, you can identify

forward looking statements by terms such as "may," "will," "should," "expect," "plan,"

"anticipate," "could," "intend," "target," "project," "contemplate,"

"believe," "estimate," "predict," "potential" or "continue" or the negative

of these terms or other similar expressions, although not all forward-looking statements contain these identifying words. All statements

contained in this press release that do not relate to matters of historical fact should be considered forward-looking statements, including

without limitation, statements regarding: positioning ARCALYST as the standard of care for recurrent pericarditis with the goal of broadening

our reach and helping even more patients; our ability to execute on synergistic growth opportunities across our portfolio, including

the expansion of our ARCALYST cardiovascular franchise; our expectation that (i) the proof-of-concept portion of the Phase 2 clinical

trial of KPL-404 in rheumatoid arthritis will begin after completion of the multiple ascending dose portion of such trial, and (ii) we

will report data from such Phase 2 clinical trial in the first half of 2024; our pursuit of collaborative study agreements to evaluate

the potential of mavrilimumab in rare cardiovascular diseases where the GM-CSF mechanism has been implicated; our expectation that ARCALYST

net revenue for full-year 2022 will be between $115 million and $130 million; our expectation about our cash reserves funding our current

operating plan into at least 2025; our beliefs about the mechanisms of action of our product candidates and potential impact of their

approach, including that using KPL-404 to disrupt the CD40-CD154 interaction is an attractive approach to address multiple autoimmune

disease pathologies; and our belief that all of our product candidates offer the potential for differentiation.

These forward-looking

statements are based on management's current expectations. These statements are neither promises nor guarantees, but involve known

and unknown risks, uncertainties and other important factors that may cause our actual results, performance or achievements to be materially

different from any future results, performance or achievements expressed or implied by the forward-looking statements, including without

limitation, the following: delays or difficulty in enrollment of patients in, and activation or continuation of sites for, our clinical

trials; delays or difficulty in completing our clinical trials as originally designed; potential for changes between final data and any

preliminary, interim, top-line or other data from clinical trials; our inability to replicate results from our earlier clinical trials

or studies; impact of additional data from us or other companies, including the potential for our data to produce negative, inconclusive

or commercially uncompetitive results; potential undesirable side effects caused by our products and product candidates; our inability

to demonstrate safety and efficacy to the satisfaction of applicable regulatory authorities; potential for applicable regulatory authorities

to not accept our filings, delay or deny approval of any of our product candidates or require additional data or trials to support approval;

inability to successfully execute on our commercial strategy for ARCALYST; our reliance on third parties as the sole source of supply

of the drug substance and drug product used in our products and product candidates; our reliance on Regeneron as the sole manufacturer

of ARCALYST; raw materials, important ancillary products and drug substance and/or drug product shortages; our reliance on third parties

to conduct research, clinical trials, and/or certain regulatory activities for our product candidates; complications in coordinating

requirements, regulations and guidelines of regulatory authorities across jurisdictions for our clinical trials; the impact of the COVID-19

pandemic and any subsequent pandemic and measures taken in response to such pandemics on our business and operations as well as the business

and operations of our manufacturers, CROs upon whom we rely to conduct our clinical trials, and other third parties with whom we conduct

business or otherwise engage, including the FDA and other regulatory authorities; changes in our operating plan and funding requirements;

and existing or new competition.

These and other important

factors discussed in our filings with the U.S. Securities and Exchange Commission, including under the caption "Risk Factors"

contained therein, could cause actual results to differ materially from those indicated by the forward-looking statements made in this

press release. Any such forward-looking statements represent management's estimates as of the date of this press release. Except

as required by law, we disclaim any intention or obligation to update or revise any forward-looking statements. These forward-looking

statements should not be relied upon as representing our views as of any date subsequent to the date of this press release.

a registered trademark of Regeneron Pharmaceuticals, Inc. All other trademarks are the property of their respective

Kiniksa Investor and

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